An intervertebral disc is a soft tissue compartment connecting the vertebra bones in a spinal column. Each healthy disc consists of two parts, an outer annulus fibrosis (hereinafter “the annulus”) and an inner nucleus pulposes (hereinafter “the nucleus”). The annulus completely circumscribes and encloses the nucleus. The annulus is connected to its adjacent associated pair of vertebrae by collagen fibers. The intervertebral disc is an example of a soft tissue compartment adjoining first and second bones (vertebra) having an initial height and an initial width. Other joints consisting of a soft tissue compartment adjoining at least first and second bones having an initial height and an initial width include the joints of the hand, wrist, elbow, shoulder, foot, ankle, knee, hip, and the like.
Typically, when a disc is damaged, the annulus ruptures and the nucleus herniates. Discectomy surgery removes the extruded nucleus, leaving behind the ruptured annulus. The ruptured annulus is, by itself, ineffective in controlling motion and supporting the loads applied by the adjacent pair of vertebrae. With time, the disc flattens, widens, and bulges, compressing nerves and producing pain. Uncontrolled loads are transmitted to each vertebra. Each vertebra tends to grow wider in an attempt to distribute and compensate for higher loads. When a vertebra grows, bone spurs form. The bone spurs further compress nerves, producing pain. In response to damaged discs, especially herniated disks, a variety of intervertebral devices are disclosed in the art to replace the intervertebral disc. Such devices are implanted intermediate an adjacent pair of vertebra, and function to assist the vertebra. These devices do not assist the intervertebral disc. In fact, in many cases the disc is removed. Insertion of these devices has heretofore been complicated, problematic, and usually performed blindly or with only fluoroscopy or other radioimaging techniques.
In view of the foregoing, it would be advantageous to have implantation devices, systems, and methods that allow for visualization of the disc as well as the implantation of a medical device between adjacent vertebra using endoscopy.